Effect of High Operating Temperatures on the Wear Characteristics of Boron Carbide and Ilmenite Reinforced LM13 Alloy-Based Composites

Abstract

Wear properties of LM13 alloy-based composites were studied by using boron carbide (B4C) and ilmenite particles (FeTiO3) separately as reinforcement. The different weight percentage of reinforcement (5 wt%, 10 wt%, and 15 wt%) was added to the base alloy through stir-casting. A comparison of B4C reinforced composites (LB composites) and FeTiO3 reinforced composites (LI composites) was done on the basis of interfacial bonding, refinement/morphology of eutectic silicon, friction, and wear behavior (both at room temperature and elevated temperature conditions). Microstructural analysis revealed uniform distribution of ceramic particles in the matrix. Significant reduction in grain size and change in morphology was obtained for LB composites whereas strong interfacial bonding was obtained for LI composites. Higher hardness, lower wear-rate, and higher coefficient of friction (COF) values were shown by LB composites. A decrease in COF for LI composites (at room as well as high temperatures) corresponded to the lubricity effect of ilmenite particles. At room temperature, wear track and debris showed a change in wear mechanism from abrasive to delamination wear with an increase in load from 10 N to 50 N. Under elevated temperature conditions, these mechanisms were combined with oxidation wear.